Did the Prevalence of Disability in France Really Fall Sharply in the 1990s? A Discussion of Questions Asked in the French Health Survey

Article excerpt

For nearly thirty years now, statistical surveys on the health status of the general population have extended in scope beyond disease and medical consumption to include measures of disability. At a time of general mortality decline when people can expect to live for longer with illness and disability, their goal is to evaluate quality of life, autonomy, and social participation. Initially focused on seniors' health, disability questions now cover the population as whole. They are ever more numerous and detailed, providing a fuller description of disabilities and of respondents' reliance on assistive devices or assistance from their contact circle so as to improve understanding of current and future needs in this area.

Recent international data broadly indicate a decrease in disability in the 1990s, concurrent with a rise in life expectancy (Robine et al., 1999; Robine et al., 2003; Crimmins, 2004). For example, the prevalence of disability at all levels has been declining steadily among U.S. seniors (Freedman et al., 2002), though more slowly at the oldest ages (Schoeni et al., 2005). It is accompanied by a decrease in reliance on personal care assistance among people aged 70 or over (Freedman et al., 2004). Studies show a comparable fall in disability in Europe as well, for example in Sweden (Lagergren and Batljan, 2000) and Denmark (Bronnum-Hansen, 2005).

In France, a general question on disability - more specifically, on being hampered or disabled - was introduced in the ten-year Health Survey of 19801981 and repeated in 1991-1992. Analyses have shown a decrease in disability in the 1980s, both at all levels and at severe levels only (Robine and Mormiche, 1994). In the same interval, findings show an increase in reporting of certain illnesses but a loosening of their link to disability (Robine et al., 1998). The being hampered or disabled question was again included in the 2002-2003 survey, so it should be possible to track ongoing change. The raw results suggest a sharp drop in disability between 1991-1992 and 2002-2003 which, though expected, exceeds the most optimistic forecasts. To explain this finding, we explored the factors that may have contributed to this trend.

The substantial modifications in the 2002-2003 survey protocol may have "changed the nature" of the being hampered or disabled question and exaggerated the decline in measured disability. The question was moved to a different position, so its environment and the guidelines for responding to it were changed. Given the question's subject and wording, it may have been sensitive to the new survey design. Our paper uses various data sources and disability indicators to discuss this hypothesis.

Part one describes the context of our study and the data. Part two gives a detailed presentation of the results obtained with the being hampered or disabled question in the three Health Surveys and the sharp decrease observed in the 1990s. In part three, postulating a change in the way the being hampered or disabled question was answered, and, consequently, in the characteristics of the population that it identifies, we describe the population using the other disability indicators available in the 2002-2003 survey. We conclude by offering some possible explanations for the steep fall in reported disability between the 1991-1992 and 2002-2003 surveys.

I. Context of our study

The universe of disability is complex. Broadly speaking, it encompasses the consequences of illness and accidents on people's daily life and on their social integration. "Disability" is a generic terms that cover different dimensions such as self-perceived disability, functional health, need for help in everyday activities, and administrative recognition. These dimensions overlap only in part (Ravaud et al., 1999; Ravaud et al., 2002). Each describes a specific aspect of disability; some from a medical angle (such as impairments and functional limitations), others from a more social angle (such as administrative recognition, insurance coverage and social participation). …